A polarizing moment in U.S. history occurred last night (Nov. 24), when a Ferguson, Mo. grand jury failed to indict Darren Wilson, the officer responsible for killing unarmed black teen Michael Brown on Aug. 9.

The controversial decision not to take Wilson to trial ignited nationwide outcry as everyone from local citizens to politicians to artists like Pharrell and Rihanna to spoke out about the shortcomings of the American justice system.

Killer Mike, one-half of Run the Jewels, is one of the many hip-hop stars that have been extremely vocal about the Brown tragedy. Several days after Brown's death, the rapper wrote an open letter about the incident, urging America to see pass class and race. He also penned a powerful op-ed for Billboard, touching on constitutional rights and police brutality.

Run the Jewels happened to be performing in St. Louis on Monday evening, mere miles away from the unrest in Ferguson. When Mike heard that prosecutor McCulloch announced Wilson would not be indicted for killing Brown, the rhymer gave an emotional eye-opening speech before his performance at the venue. Mike revealed that he anticipated the grand jury’s decision, however, the news was still devastating and brought him to tears because he's scared for the lives of his own two sons.

Read Killer Mike's full speech below and watch him in action above.

I would like to say Rest in Peace to Michael Brown. I would like to give all thoughts and prayers to the people out there peacefully protesting. I also give thoughts and prayers to the people who could not hold their anger in because riots are only the language of the unhold. We usually come on to Queen’s ‘Champion’, but I just got to tell you today, no matter how much we do it, no matter how much we get s--- together, s--- comes along and kicks you on your ass. And you don't feel like a champion. Tonight, I got kicked on my ass when I heard that prosecutor. You motherf---ers got me today, I knew it was coming when Eric Holder decided to resign. I knew it wasn't gonna be good. You motherf---ers got me today. You kicked me on my ass today, because I have a 20-year-old son and I have a 12-year-old son, and I’m so afraid for them...

When I stood on the bus, and I cried, and I hugged my friend, I said, ‘These motherf---ers got me today.’ When I stood in front of my wife, and I cried like a baby, I said, ‘These motherf---ers got me today.' You motherf---ers will not own tomorrow, we will not bend to your fear, we will not accept your pain, we are not going to keep playing that race card, because we know you don’t value my skin. We know you do value his [El-P], but we’re friends and nothing is going to devalue that.

There was no peace in my heart and I wanted to walk out to ‘Burn This Motherf---er Down.' But I got to tell you, I’m from Atlanta, Ga., something said, ‘Just look for something [Martin Luther King, Jr.] might have said,’ so I googled Martin King and Wikipedia popped up, and he was 39 years old when you motherf---ers killed him. He was the same age as I am, the same age as [El-P]. He was a young man when they killed him.

But I can promise you today: If I die when I walk off this stage tomorrow, I’ma let you know this: it is not about race, it is not a class, it is not about color, it’s about what they killed him for. It is about poverty, it is about greed, and it is about a war machine. It is about a war machine that uses you. So as I go tomorrow, I might go the day after, but the one thing I want you to know it is us against the motherf---ing machine!”

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